Fastest planes on the least amount of HP

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atypicalguy

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It doesnt make much sense to have this discussion about efficiency without controlling for gross weight, as the fai does already.
 

Victor Bravo

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BTW, those Formula One 200 CI Reno racers kick out around 150 HP at 4,500 - 5,000 RPM and only last for about 10 minutes.
Nooo. The stock valves will float on the O-200 at those RPM's, and you will not get anything useful out of it. The IF1 rules specifically do not allow different springs or lighter valves. I got 4200-4300 out of my O-200, built by a good race engine builder (Randy Musser, a former Lycoming QC inspector and race builder). Alan Preston once told me he managed to get 4400 out of Judy/Sitting Duck at high density altitude in Reno once, but I never heard that anybody got over 4500. Jim Miller had run a smaller prop when he was running that ducted fan in Pushy Cat, and didn't g et anything useful out of trying to turn it faster.

The O-200 race engines lasted a lot longer than 10 minutes, but still far far less than in any normal RPM/temperature circumstance. Maybe 5-10 hours is my guess, which is a lot. The reason for this is because the original rules were written and maintained specifically to prevent "hand grenade" race engines, because the Goodyear/F1 class was intended from the start to be for the "average guy" (sorry, you too Kathy Gray :) ) to be able to afford. The wise old men who designed these rules 75 years ago set a lot of limits on part weights, stock parts, all components "must function in the normal manner", etc. etc.

It's been over 30 years since I was involved, and I understand that they allow electronic ignition now, which is pretty cool. Significant power and reliability improvement without a huge cost increase, and (I hope) a LOT safer to start the !(#*$ engine without chopping someone's hand off with those sharp carbon blades.
 

Rhino

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We could start our own thread, but that could very well be a Pandora's box.
 

Lendo

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FW, I think you need to be a little more specific, single seat, 2 seat etc. Light Single Seat Aircraft can go very fast on a much less HP, however rage may be severely limited due to low fuel capacity - It's all relative.
George
 

Brünner

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I know what you might be thinking, "This guy is asking about efficiency", and I suppose I am, but I'm not curious about MPG. MPG conversations always end up with Gliders or PPG's, and that's not what I'm after.

I'm more curious if anyone knows the fastest aircraft that have <80hp, <100hp, <150hp? The Reno Air Races seem like a good starting point, but then I hear about things like the Tailwind, TL Stream, Facet Opal... heck, even the Varieze seems like it belongs in this class of aircraft. Efficiency and speed.

Mile-per-hour, per-horsepower?
And I'd like to add: easiness of construction?
 
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